So I picked up this gem today for the sum of a case of Coors Light. It's pretty complete but rough. The good thing is the motor turns over and seems like it has OK compression and it will shift through the gears. Are these 5 speeds? Also the shift shaft is loose, and I am confused about the the splined shaft right below it- looks like it comes through the frame? Also it appears the swingarm has been lengthened very crudely. I have a Bultaco Sherpa T for competition, but thought it would be fun to fix this one up. One of the guys I ride with has one and he does really good on it. Any comments or opinions appreciated.

So I picked up this gem today for the sum of a case of Coors Light. It's pretty complete but rough. The good thing is the motor turns over and seems like it has OK compression and it will shift through the gears. Are these 5 speeds? Also the shift shaft is loose, and I am confused about the the splined shaft right below it- looks like it comes through the frame? Also it appears the swingarm has been lengthened very crudely. I have a Bultaco Sherpa T for competition, but thought it would be fun to fix this one up. One of the guys I ride with has one and he does really good on it. Any comments or opinions appreciated.

From someone who's "been there done that" twice Starting with a $20 investment isn't so bad. If the motor proves solid, get a gear change kit from tytrials in the UK for under $150 or find a machinest who likes Coors light, fenders from dcplastics, some paint and decals and have fun.
When I got my 1st TY175 I also wondered what the deal was with the splined piece on the frame. I never found out what it was for , I worried that I had bought a pieced together frankenbike.
My problem locally is to find enough interest in a twinshock class to even have 2-3 riders.

Just completed a project on a 75 back in June. A week after I got it running I competed in a local twinshock event on it and had a lot of fun. I've got a modern montesa too. I'm surprised at how good a trials bike the little ty is, though I'm by no means an expert. tytrials in the uk has just about anything you might need and bjracing is also a good source. there are some others on this side of the pond too.

This is how it came to me.

It turned out really nice I think. It will never bring what I have in it, but it did win a local vintage show in the old dirt bike class. I had a great time doing it and riding it is a hoot too.

So I have started the disassembly and have discovered some nasty things! I got the swingarm off and see that the previous owner welded another tube in front of the main tube on the swingarm to lengthen it. So now I am in search of a good swingarm. The rear sprocket has been customized. You can make just about anything fit if you try hard enough. So new rear sprocket as well.